Gladstone Harbour.
Gladstone Harbour. Brenda Strong

Link between dredging and aquatic disease still in dispute

Fisheries Queensland's response on the spill

Animals still showing signs of stress according to aquatic veterinarian

FISHERIES Queensland is standing by its belief that the spilling of Awoonga Dam in 2010-11 was the major cause of fish disease in Gladstone Harbour that year.

The question of what caused fish disease in 2011 is at the heart of a dispute between Gladstone Ports Corporation and commercial fishermen in the region, who believe dredging is to blame.

A Fisheries spokeswoman yesterday said while most of the Queensland coast had seen massive influxes of freshwater causing ecological problems, the impacts of the floods in Gladstone had an additional problem.

"In Gladstone, it is not just the freshwater influx impact on the ecosystem that was identified as contributing to fish ill health, but also the resulting overspill of 30,000 barramundi and other fish species from Awoonga Dam into the surrounding waterways," she said.

"The large number and size of fish from the dam flowing into the relatively small Boyne River created conditions that were unique to the Gladstone region and were not reported anywhere else along the Queensland coast."

Fisheries Queensland response on the spill

"This influx of a significant number (barramundi) would have had major impacts upon the food chain and this imbalance would have impacted upon the ecosystem, including all fish... particularly the physical stress from the fall (over the Awoonga Dam), the subsequent competition for food and then coping with winter temperatures, which would (lower) fish immune systems and susceptibility to ill health."- Fisheries Queensland

Animals still showing signs of stress according to aquatic veterinarian

THE critical report linking fish illness to dredging in Gladstone Harbour is still at the centre of intense argument.

Aquatic veterinarian Dr Matt Landos found aquatic animals in Gladstone Harbour remained in poor health and the problem was most likely caused by the Western Basin Dredging and Disposal Project.

Fisheries Queensland yesterday rejected both those points, saying fish health was "much improved" from the controversial period in 2011.

The question of whether fish in the harbour are still sick is at the heart of an ongoing dispute.

Dr Landos said he collected samples of various species, including crabs, fish, sharks and stingrays, and found ongoing health problems.

Among other indicators, Dr Landos said examining the internal organs of catch showed signs of stress.

He said mud crabs in particular showed clear signs of stress.

Click here to read Dr Landos's report.

Click here for more reports on Gladstone Harbour.

Aquatic Veterinarian Dr Matt Landos handed his report to the Gladstone Fish Research Fund at the Gladstone Fish Market yesterday. Photo Christopher Chan / The Observer
Aquatic veterinarian Dr Matt Landos. Christopher Chan